The Influence of Observation Time on the Role of the Product Design in Consumer Preference

Maridlle E.H. Creusen, Delft University of Technology
Jan P.L. Schoormans, Delft University of Technology
ABSTRACT - The product design influences consumer preference in several ways. This influence depends on the product observation time of consumers, as this influences the opportunity to pay attention to the product. In an experiment, the influence is regarded of product observation time on the beliefs based on the product design, that underlie preference. Observation time did not influence the importance of expressive beliefs, utilitarian beliefs were less important with short observation. With short observation, most utilitarian beliefs are based on salient aspects (as size) or overall product imprssion (quality-look), with long observation this basis is specific details. Implications are discussed.
[ to cite ]:
Maridlle E.H. Creusen and Jan P.L. Schoormans (1998) ,"The Influence of Observation Time on the Role of the Product Design in Consumer Preference", in NA - Advances in Consumer Research Volume 25, eds. Joseph W. Alba & J. Wesley Hutchinson, Provo, UT : Association for Consumer Research, Pages: 551-556.

Advances in Consumer Research Volume 25, 1998      Pages 551-556

THE INFLUENCE OF OBSERVATION TIME ON THE ROLE OF THE PRODUCT DESIGN IN CONSUMER PREFERENCE

Maridlle E.H. Creusen, Delft University of Technology

Jan P.L. Schoormans, Delft University of Technology

ABSTRACT -

The product design influences consumer preference in several ways. This influence depends on the product observation time of consumers, as this influences the opportunity to pay attention to the product. In an experiment, the influence is regarded of product observation time on the beliefs based on the product design, that underlie preference. Observation time did not influence the importance of expressive beliefs, utilitarian beliefs were less important with short observation. With short observation, most utilitarian beliefs are based on salient aspects (as size) or overall product imprssion (quality-look), with long observation this basis is specific details. Implications are discussed.

INTRODUCTION

The importance of product design for product sale success is widely acknowledged. Design will become increasingly important as an opportunity to differentiate a product in the marketplace, because other marketing tools become more expensive (Kotler and Rath 1983) and differences in technology between products become smaller (e.g. L÷bach 1976; Pilditch 1976; Veryzer 1995).

Different definitions of product design exist. Here, we focus on design as (a plan for) the physical execution of a product, that is, a particular product configuration (i.e. arrangement of elements or parts, see Veryzer 1995). The technical functions of a product are executed in a certain design (consisting of shape, colour and texture), but the design also has functions of its own, as it can have aesthetic and symbolic value. In order to make an optimal use of design as a marketing tool, insight is needed into the role that the product design (i.e. appearance) can have in consumer product evaluation, and thus preference.

ROLES OF A PRODUCT DESIGN IN CONSUMER PREFERENCE

The product design can influence consumer product preference in different ways. Recently, several authors considered the role of the package or product appearance on consumer product evaluation or choice (Bloch 1995; Garber 1995; Veryzer 1993, 1995). Also in literature about industrial design, attention is paid to the role of design in the consumer-product interaction. [Lobach (1976, p.20) defines industrial design as the process of adapting products that are to be industrially manufactured to the physical and psychological needs of users.] On the basis of this information, the following roles (influences) of design in product preference can be distinguished: attention drawing ability, easiness to categorize, and basis for the formation of beliefs about practical, ergonomic, hedonic and symbolic product value.

The ability of a design to draw attention, and the typicality of the design (which influences the easiness to categorize) influence preference indirectly, as they may influence the composition of the consideration set of consumers. Garber (1995) states that visual typicality (defined as sharing of visual attributes) and visual novelty of the package appearance for fast moving consumer goods determine whether a product alternative is included in the 'attention’ set, from which the consideration set is formed. It is likely that the same effect applies to product design. Visual novelty pertains to the ability of a design to draw attention, a role of design that is also mentioned by Bloch (1995) and L÷bach (1976). Visual typicality influences the easiness to categorize a product, as the product form may be used for categorization (Bloch 1995; Veryzer 1995). When a consumer has a very low level of motivation, ability or opportunity to process product information, preference may even follow directly from categorization (Cohen 1982; Sujan 1985). In such a case, a product may be chosen because it is typicalfor the (sub)category, or resembles a well-known exemplar (e.g., the product currently owned). [Although the findings of Sujan (1985) pertain to typicality of verbal information, we expect the same for visual typicality.]

Further, a design can have practical, ergonomic, hedonic or symbolic value for the consumer. The practical role of a design for consumers (L÷bach 1976; Veryzer 1995) pertains to the utilitarian function(s) that a product can perform, i.e. to what you can do with the product. Technical options are an example hereof. The ergonomic role (L÷bach 1976; Schnrer 1971; Veryzer 1995) [Lobach (1976) ranges this under the aesthetic function, and Veryzer (1995) calls it the communicative aspect of a design.] entails the adjustment of a product to human qualities, the amount in which the product is suited to perform and communicate its practical function(s), thus the easiness of use. The hedonic role entails the ability of a design to provide sensory pleasure, to give the consumer a 'good feeling’ (Bloch 1995; L÷bach 1976; Veryzer 1995). Aesthetic considerations (e.g., looks attractive) are one example hereof. The symbolic role (L÷bach 1976; Schnrer 1971) pertains to the psychologic and social aspects of product use, which follow from relating former experiences and feelings to the product.

THE INFLUENCE OF OBSERVATION TIME ON THE ROLE OF DESIGN FOR CONSUMERS

Consumers differ in their motivation and ability to process product information, while situational factors may impact the opportunity to perceive or process product information. Such restraints on the motivation, opportunity or ability (MOA) to process product information will result in a different way of product evaluation. This means that the design may have a different role in this process. Factors like time pressure and lack of motivation are typical of many consumer situations (Alba and Hutchinson 1987). Also, many purchases take place without an extensive evaluation of alternatives, even major ones (Olshavsky and Granbois 1979). Therefore it is important to take the influence of information processing restraints into account in order to get a realistic insight into the influence of the design on consumer preference.

More attention to the product information and more allocated processing capacity create the potential for deeper (more intense) processing (MacInnis and Jaworski 1989). A limitation of the product observation time will therefore result in more superficial processing, as the consumer has no opportunity to pay a lot of attention to the product. In this study, we use the limitation of product observation time to get insight into the influence of processing restraints on the role of the product design in consumer preference.

With unrestricted product observation time, the probability will rise that beliefs about several aspects (practical, ergonomic, hedonic or symbolic) play a role in preference, as there is more time to judge several product aspects. But will the kinds of beliefs that underlie preference differ depending on the product observation time?

Hypotheses

Depending on the kind of motivation (i.e. involvement) underlying a purchase, consumers pay attention to different product attribues (Claeys, Swinnen, and Vanden Abeele 1990; Mittal 1987). This motivation may be utilitarian and/or value-expressive (Park and Mittal 1985). [Note that products often have both utilitarian as well as expressive importance for the consumer (see Mittal 1988, or Ratchford, 1987).] According to the utilitarian motive, a consumer is concerned with the cost-benefits rendered, and the functional performance of a product. Roles of a design for consumers that relate to this motive are the practical and the ergonomic role. According to the value-expressive motive, a consumer is interested in enhancing self-esteem and in projecting his/her desired image upon others through the use of the product. Roles of a design for consumers that relate to this motive are the hedonic and the symbolic role.

The kind of motivation underlying a purchase is often posited to be related to the kind of information processing that will be used to evaluate the product (e.g., Ratchford 1987). Expressive motivation will promote processing by the right hemisphere of the brain, which is a gestalt-like, holistic kind of processing. Image dimensions of the product will be important to the consumer. Utilitarian motivation will lead to left-brain, analytic processing. Information about specific, disparate product features will be important to the consumer (Mittal 1987). In relation to product design, this would mean that symbolic and hedonic (expressive) aspects tend to be judged holistically, while practical and ergonomic (utilitarian) aspects tend to be judged analytically.

Therefore we expect that expressive beliefs will be based on the overall impression of the product design (instead of on specific details of the design). The overall impression can be quickly perceived, which means that expressive beliefs can also be formed when the product observation time is short.

H1 The number of subjects that mention expressive product beliefs as a basis for their product preference will not differ between conditions of short or long product observation time

As utilitarian aspects tend to be judged analytically, they will be based on specific details of the product design. The perception of product details will deteriorate when the product observation time is short. Therefore, we expect that less preferences will be based on utilitarian beliefs when the product observation time is short.

H2 More subjects will mention utilitarian product beliefs as a basis for product preference when the product observation time is long as compared to short

In addition, we expect that utilitarian attributes will be evaluated differently in conditions of short and long product observation time. Specific details will be difficult to perceive when the observation time is short, as there is little opportunity to pay attention to the product. This means that subjects have to form utilitarian beliefs in some other way. As opportunity and ability moderate the influence of involvement (motivation) on the intensity of processing (MacInnis and Jaworski 1989), the effect of low product observation time will be comparable to the effect of low involvement. It is often assumed that low involved consumers will use right brai (holistic) processing, because this costs less effort than analytic processing (e.g. Hansen 1981). This means that when the product observation time is short, utilitarian beliefs may be based on the overall impression of the product (holistically), as first impressions and associations can be easily and quickly perceived. A product design may for example communicate a high quality image. However, attention to a few salient specific features is also posed to occur in conditions of low involvement, ability, or opportunity (MacInnis and Jaworski 1989; Mittal 1987; Ward and Scott 1987). In these cases analytic processing takes place, although in a lesser degree, in that features are not weighted but only one or two salient features play a role. So we expect that when the product observation time is restricted, utilitarian beliefs will be based on a few salient characteristics of the design, or on the overall impression that the product design communicates. When the product observation time is long, utilitarian attributes will be evaluated on the basis of detailed aspects (features) that can be perceived on basis of the product design. This leads to our third hypothesis:

H3 More subjects will base their utilitarian beliefs on details of the product design when the product observation time is long as compared to short

Further, when observation time is short, saliency (attention drawing) and typicality of the design will probably have a bigger influence on preference. Salient features are defined as the ones that are most prominent, noticeable or conspicuous (MacInnis and Jaworski 1989). When the design looks (visually) typical, this heightens the probability that choice will be directly based on categorization. So when a certain product is generally purchased in conditions of low MOA, the recommendation for the product design would be to emphasize certain differences compared to other product alternatives, but not differ too much, because then categorization may not take place successfully (see Schoormans and Robben 1997). When the product observation time is long, saliency and typicality are less likely to influence product choice, as the consumer puts more time into the decision and thus is more likely to 'look beyond’ this.

H4 More subjects will mention the ability of the product design to draw attention and the typicality of the design as reasons for their preference when the product observation time is short as compared to long

METHOD

An experiment is performed in whic we looked at the different roles of the product design in product preference in conditions of short and longer product observation. Product observation time is varied by using a short and a longer presentation time of the product alternatives, by means of a tachistoscope. Out of two product alternatives, subjects indicated the alternative they preferred. The way in which the design played a role in the preference is assessed by means of an interview. The interviewer first asked the subject to mention the reasons underlying her product preference ('why do you prefer product X?), and then probed until it was clear for every reason (belief) that the subject mentioned how it was formed and why it is valued.

Pilot Study

A pilot study (N=120) is performed in order to determine the presentation time at which subjects have enough time to perceive the product alternatives (i.e. their overall appearance and salient attributes), but not enough time to look at them in detail. Six presentation times, ranging from 100 to 4000 msec, are tested. Each subject saw four slides, each with different products and at a different presentation time. The order of the presentation times, increasing or decreasing, was alternated between subjects. The time at which almost all subjects correctly perceived the overall forms, but only few subjects perceived some details (which is determined by means of a questionnaire), is determined at 800 msec. Subjects were selected from the same consumer household panel as in the main study, but were excluded from participation in the main study.

Subjects

Subjects are members of a consumer household panel. In total 127 subjects participated in the experiment. [Only data for 109 subjects for clock radio and 107 for hairdryer are available, because several interviews are not recorded on audio tape by accident.] All subjects are female, due to the requirements of an experiment in which the subjects participated immediately following this one. Their ages range from 23 years to 56 years and their education level ranged from primary school level up to university level. The subjects received a compensation of " $ 6.

Materials

Two well known products are used: clock radio and hairdryer. For each product three product alternatives are used, which were bought in local shops.

The product alternatives are presented in pairs on a colour slide, with use of a tachistoscope. To avoid position influences, the left-right position of the products on the slides is alternated. This results in six slides per product (three pairs, positions alternated).

Design

Two conditions are used, one with short presentation of the choice alternatives (800 msec.), and one with long presentation (90 sec. or until the subject said it was long enough). Subjects indicated their preferred product alternative for each of the two products. One of the preferences is formed after short presentation, and one after long presentation of the alternatives. The order of the conditions (short or long presentation), the order in which the products are judged (clock radio-hairdryer or hairdryer-clock radio), as well as the left-right position of the product alternatives on the slide, are covaried systematically over subjects.

Procedure

The subject was seated behind a table and in front of a screen on which the slides are projected. To let the subject get used to the short presentation time, a practice slide (with two thermos flasks on it) was presented immediately before the slide in the short condition. A green slide was projected whenever no product slide was presented, so subjects knew where to look, and their eyes did not have to accommodate to the change in light-intensity.

After presentation of the first slide, the subject indicated her preferred product alternative (by marking 'the left’ or 'the right’ one on an answer sheet). She then filled in a short questionnaire about the kind of processing she has used: holistic and/or analytic (not reported here). Next, the subject was interviewed about the reasons underlying her preference, until for each reason it was clear why it was valued and on what information it was based. For example, when someone mentions size, this may be valued either for aesthetic or ergonomic reasons (e.g., needs less space). As the design roles are the basis for the categorization, and not the product characteristics, the interviewer has to get this clear. This interview was recorded on audio tape. After this, the second slide was presented, followed by the same procedure. At the end some additional data were collected (which are not reported in this paper). Next, the subject participated in another experiment. Subjects were debriefed afterwards.

RESULTS

Categorization of choice reasons

The trnscriptions of the interviews form the basis for the data analysis. Two judges (including one of the authors) coded the bases for the preference of each subject, by looking at the considerations that subjects mention as causes for their preference. For each kind of design influence (attention drawing ability, typicality, practical value, ergonomic value, hedonic value, or symbolic value) it is coded whether it was a basis for the preference or not (binary data). A preference can be based on several of these reasons. The judges also noted down the product characteristics on which each reason is based (e.g., the ergonomic reason 'better in use’ may be based on the number of buttons, or on the size of the handle). These are later grouped into 'based on details’ (like display or handle) or 'based on overall impression or salient aspects’ (like quality-look, colour or size), in order to test hypothesis 3.

Some subjects are left out of the analysis because they possessed one of the clock radios (1) or hairdryers (8) that was presented to them. Data for 4 subjects for clock radio and 5 for hairdryer were excluded because the interviewer had not asked enough clarification for one of the preference reasons, so the basis for the choice remained unclear. This leaves us with data of 104 subjects for clock radio, with an equal number in each condition, and 100 subjects for hairdryer, of which 45 in the short observation condition.

The results of the categorization procedure are listed in Table 1. In the long observation condition, 4 subjects for clock radio, and 3 for hairdryer mentioned brand name as a choice reason. As this does not pertain to the product design as such (as it is verbal information), we will further disregard it. Differences in the number of subjects that mentions each kind of design role between conditions are tested by means of Chi-square tests. Significant differences are indicated in the table. Reasons that are coded as practical pertain to the number of technical possibilities that the product has (e.g., has more buttons and will therefore have more possibilities), or the impression about technical quality (e.g. gives a more durable impression to me). Ergonomic reasons are mostly based on the easiness of use of product parts like buttons, displays or handles (e.g., display is easy visible, large green button which can be easily found in the dark), and on the size and colour of the product as a whole (e.g. easy to store, better to see). Hedonic reasons pertain to the attractiveness of the design and whether it will fit into the home environment (e.g., looked more attractive as a whole, I was immediately attracted to it). Symbolic reasons pertain to the 'meaning’ that the design communicates (e.g., gives a cosy impression, looks cheerful or friendly). Reasons like 'drew my attention’ fell into the 'attention drawing’ category, and reasons like 'looks more like a hairdryer’ and 'resembles the one I have at home’ are coded in the 'typicality’ category.

TABLE 1

NUMBER OF SUBJECTS MENTIONING EACH DESIGN ROLE

The judges initially agreed on the codings for 66 % of the subjects for hairdryer, and 70 % for clock radio. However, some differences between judges were systematic. One of the judges consistently coded a professional look (for hairdryer) as a symbolic reason. But as all subjects mentioned that this led them to infer that the product was more reliable or durable, their choice was clearly based on practical (utilitarian) grounds. Further, as symbolic and aesthetic reasons are often linked (e.g., looks friendly and attractive), often only one of them was coded when they were mentioned both. When these systematic differences are accounted for, the judges agreed on 88 % of the subjects for clock radio, and 83 % for hairdryer. The remaining differences were mostly due to the accidentally omitting of some codings (some interviews were rather lengthy), and in discussing the differences the judges agreed completely.

Tests of the hypotheses

According to Hypothesis 1, the number of subjects that mentions expressive reasons does not differ between conditions. This is indeed found (clock radio: c2=.30, df=1, p=.59; hairdryer: c2=.08, df=1, p=.78) [The p-values are listed here, as this is not a statistical test in the classical sense. This is because our alternative hypothesis states that there is no difference, and we cannot test the null hypothesis that there is a difference, as this difference cannot be quantified. The p-values listed here give the probability that the alternative hypothesis is true, and as these values are rather high, this supports our hypothesis that there are no differences.] so hypothesis 1 is not rejected.

According to Hypothesis 2, the number of subjects that mention utilitarian reasons is expected to be higher in the long observation condition. This is indeed the case (clock radio: c2=11.12, df=1, p<.001; hairdryer: c2=17.07, p<.001). So hypothesis 2 is supported.

According to hypothesis 3, utilitarian reasons in the long observation condition are more often based on details of the product design. To test this, the ergonomic and practical reasons are further specified into whether they are based on details or not (the latter means based on the overall product impression or on salient aspects like size or colour). Like hypothesized, more subjects mention utilitarian reasons based on details (like buttons or display) in the long observation condition (short vs. long condition: 4 out of 18 vs. 25 out of 35 for clock radio, c2=11.62, p <.001; 5 out of 26 vs. 25 out of 51 for hairdryer, c2=6.43, p=.01). This supports hypothesis 3.

Hypothesis 4 poses that attention drawing ability (e.g., attracted my attention) and typicality of the design (e.g., looks more like a hairdryer, looks familiar) more often underlie preference in the short observation condition. Only a few subjects mention these roles, all in the short observation condition. The difference is only significant for typicality of the design for hairdryers.

To check for order effects (learning or demand effects), we looked whether the same results are found when we only take the first task of respondents (which halves the number of subjects). For hairdryer the results remain the same, except for the difference for typicality, which is not significant anymore due to the decrease in subjects. For clock radio the difference in the number of subjects mentioning utilitarian reasons becomes smaller (p=.11), although there is still a trend. When we take only the second task of respondents, all effects are the same as the ones found in Table 1, except again for typicality for hairdryer.

CONCLUSION AND DISCUSSION

In this study, we looked at the reasons for consumer product preferences which are formed on basis of the product design. We compared these reasons for preferences formed after short observation of the product alternatives (so no details can be perceived) and after long observation.

Expressive reasons are found to play an important role, as many subjects in both conditions mentioned them to underlie their preference. As expressiveness of a product leads to holistic processing (e.g., Mittal 1988), which can take place quickly and effortless, we proposed that expressive aspects play a role in the preference regardless of whether the observation time is short or long. This was indeed found.

Utilitarian reasons were mentioned by more subjects in the long observation condition. This supports the notion that subjects tend to judge utilitarian aspects analytically, for utilitarian beliefs are mentioned less when there is little opportunity to perceive details. However, still a sizable number of subjects mention utilitarian reasons in the short observation condition. The way in which these utilitarian beliefs are formed differs from the way in which they are formed in the long observation condition. In the latter condition, more utilitarian beliefs are based on details of the form (like display or buttons). In the short observation condition, most utilitarian beliefs are based on salient characteristics like colour or size (e.g., white is more clear and therefore easier in use) or on the overall product impression (e.g., has a profesional look and will therefore be of higher quality).

Typicality and attention drawing ability of the design played a minor role in determining preference. These roles will probably be bigger when there are many alternatives to choose from, instead of only two as in this study. However, as we expected they were only found to influence preference with short observation time, but this was only significant for typicality for hairdryer. The influence of typicality and attention drawing ability are often mentioned with relation to packages of fast moving consumer goods (Garber 1995, Schoormans and Robben 1997). Whether typicality and attention drawing ability of the design also influence preference for durable products is an issue for further research.

This study gives some insight into the ways in which the product design influences consumer product preference. The overall impression that the design communicates, and its salient characteristics, are found to play a big role in the formation of expressive beliefs, but also in the formation of utilitarian beliefs when there is little opportunity to perceive details. We expect that the way in which subjects use information from the product design in the short observation condition will agree with the way they use the design in conditions of low motivation or ability to process product information. This is implied by the fact that also in the long observation condition a sizable number of subjects (10 out of 35 for clock radio and 26 out of 51 for hairdryer) form utilitarian beliefs on basis of the overall impression or salient characteristics of the design. As a lack of motivation, ability or opportunity to process product information may be descriptive of many purchase situations, it is important to take the utilitarian impression that the product as a whole communicates into account in designing the product.

A limitation of this study is the artificial situation that is created in the short observation condition. This may have led subjects to take the task less seriously, which may have promoted the mentioning of very salient characteristics like colour and size. Second, presentation on a slide may make it difficult to perceive details even in the long observation condition. In a purchase situation consumers can look at the product from a shorter distance and from different angles. This may mean that the differences in beliefs between consumers with and without enough motivation, opportunity or ability to process product information may be bigger in real purchase situations. For these reasons, other methods to vary motivation, opportunity or ability to process information should also be used.

Further, in this study only visual information is presented (except for brand names or words visible on the product exteriors). It should be investigated to what extent the roles that are found in this study still play a role when also verbal information is presented, which more resembles a real life choice situation. When for example the power of a hairdryer is mentioned verbally, it is not clear whether the size of the hairdryer (which in this study is found to influence the perception of power) still plays a role in forming a belief about the power.

The product design is often saliently present in the purchase situation, and determines the first impression of the product. Also, holistic, qualitative product aspects like aesthetics, usability and a sense of quality of manufacture, are often judged on basis of the product design. These aspects can have a significant impact on marketability (Srinivasan, Lovejoy, and Beach 1997). Optimization of the design to enhance consumer preference according to one role, may damage the positive influence of other roles. For example, the use of aesthetically valued bright colours, may damage the high quality impression that the product communicates. Therefore it is important to explicitly take the different influences of the product design on consumer product preference into account.

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